Hydraulic Characteristics Study of Variable Clearance Semi-high Guide Vane Centrifugal Pump

The vane-type pressurized water chamber is one of the important components in single-stage centrifugal pumps, and it has been shown that the half-height guide vane can improve the rotational motion of the liquid flowing out of the impeller to reduce the resulting hydraulic losses. In this paper, we use the numerical simulation method combined with SST k-ω turbulence model to study the effect of variable clearance half-height guide vane on the hydraulic performance and internal flow law of centrifugal pump, focusing on the effect of variable clearance half-height guide vane on the hydraulic characteristics of centrifugal pump. The results show that the gap variation has a small effect on the hydraulic performance of the centrifugal pump under small flow conditions, and the variation becomes more and more obvious as the flow rate increases. As the flow rate increases, the head and efficiency of the centrifugal pump increase as the radial clearance of the variable clearance guide vane decreases, and the high-efficiency zone becomes wider and moves toward the high flow rate. The radial clearance of the semi-high guide vane decreases so that the head and efficiency of the centrifugal pump remain basically the same as the uniform clearance guide vane. For each flow condition of the centrifugal pump, the change of guide lobe clearance has less effect on impeller work and more effect on the change of flow field in the guide lobe and worm casing. The reduction of the radial clearance of the guide vane can effectively improve the secondary flow in the guide vane flow channel and make the flow more uniform. This study can provide a reference for the design of a semi-high guide vane centrifugal pump and improve it.